/**
 * Given a string, find the length of the longest substring without repeating characters.
 * Examples:
 * Given "abcabcbb", the answer is "abc", which the length is 3.
 * Given "bbbbb", the answer is "b", with the length of 1.
 * Given "pwwkew", the answer is "wke", with the length of 3. Note that the answer must be a substring,
 * "pwke" is a subsequence and not a substring.
 */
/**
 * @author Ivan
 *
 */
package problem3_LongestSubstringWithoutRepeatingCharacters;